Computing system



Dec. 17, 1940. L' N. K. ENGST 2,225,410

' COMPUTING SYSTEM Filed April '7, 1950 v 5 Sheets-Sheet l Dec. 17, 1940. N, K ENG T 2,225,410

COMPUTING SYSTEM Filed April 7, 1930 5 Shegts-Sheet 2.

Dec. 17, 1940. N. K. ENGST COMPUTING SYSTEM Filed April 7, 1930 5 Sheets-Sheet 3 Dec. 17,1940. T' 2, 225,41o

conru'rme SYSTEM Filed April 7, 1930 5 Sheets-Sheet 4 me. 17, 1940. ENGST 7 2,225,410

COMPUTING SYSTEM v Filed April '7, 1930 5 SheetsSheet' 5 Patented Dec. -17, 1940 UNITED ST TES COMPUTING SYSTEM Norbert K. Engst, Cicero, 111., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application April 7, 1930, Serial No. 442,103

18 Claims.

This invention relates to computing systems,

and more particularly to an electrically operated mathematical multiplication system for effecting computations, The principal object of the present invention is the provision of an efliciently operable and flex- I ible system for accomplishing mathematical computations with a minimum expenditure of effort and time and with accuracy.

In accordance with one embodiment, the invention contemplates the provision of an electrical multiplication system for multiplying five di its by three digits, in which there are seventeen sets of electrical contact disks, in nine sets of which a contact disk represents the unit number or part of the product of one digit by another digit and is provided with an associated contact brush so that the position of the disk with respect to the brush represents the, unit number 20 or part of the particular product, and in the other eight sets of which a contact disk represents the tens number or part of each particular product. One less set is provided in the tens number or part group than in the units part group since there will be no tens part of a product of any digit multiplied by one.

The multiplicand and multiplier are set up on keys which close certain electrical circuits, whereby, beginning with units, power is fed, for each digit in the multiplier, one at a time, through contacts on the disks and through distributing brushes to separate registering devices or accumulators, depending on whether the contact disks represent the units or tens part of the particular products. The distributing brushes associated with the registering device for the units part of the product transfer the electrical connections from units to tens, tens to hundreds, hundreds to ten-hundreds, etc., and simultanev ously therewith the distributing brushes associated with the registeringdevice. for the tens part of the product transfer the electrical connections from tens to hundreds, hundreds to tenhundreds, ten-hundreds to ten-thousands, etc. As soon as the separate registering devices or accumulators have received the last partial product from the contact disks a transfer circuit is automatically rendered effective for transferring the total indicated in one register into the other regv ister which will then indicate the final produ ing drawings, wherein Figs. 1, 2, 3, 4, and 5 are circuit diagrams which, when viewed collectively with Fig. 2 above Fig. 1, Fig. 3 above Fig. 2, Fig. 5 above Fig. 4 and Figs. 4 and 5 at the right of Figs. 1, 2, and 3, disclose an electrical multiplication system representing one embodiment of the invention;

Fig. 6 is an enlarged fragmentary schematic of three of the sets of contact disks representing the electrical multiplication system on the multiplying commutator;

Figs. 7 and 8 are sectional views showing 10 opposite sides of one of the contact disks illustrating the cutting of the conducting portions thereof, and

Fig. 9 is a view showing the relative location of Figs. 1, 2, 3, 4, and 5.

Referring now to the drawings in which similar parts are designated by the same numerals in the several views, it is believed that a clear understanding of the invention will be had therefrom 2o when'considered in conjunction with the follow-' ing description. In examining the circuit diagram, Figs. 1 to 5 should be arranged as shown in Fig. 9.

For the sake of clarifying the following de- 25 scription, it will be noted herein that the apparatus utilized in the circuit shown in Figs. 1 to 5 is either taken wholly from the telephone art or taken from the telephone art and modified slightly to perform slightly different functions than 30 those required of like apparatus in telephony. The disk contacts forming the multiplying commutator and which represent the partial products of one digit by another digit are adaptations of sequence switches which are well known in tele- 35 phone art. The modification in these switches consists principally in driving the switches continuously rather than intermittently, and utilizing in place of the clutches normally used with like switches in telephone practice, a relay which, upon actuation, permits current to be fed to the contact disks.

The distributor switches. and accumulator switches, which will be described in detail hereinafter, are substantially the same as the selector switches used in dial system telephony. The distributor switches comprise a plurality of brushes insulated from each other and mounted upon and insulated from a shaft which is rotatable under control of an electromagnetically operated 50 r flcation. The accumulator switches, however,

have been modified somewhat and comprise brushes having associated therewith arcuate banks of contacts. The brush individual to each i bank of contacts being connectable to a common rotating shaft at intervals by the actuation of electromagnetic clutches individual to each brush.

Referring now to Figs. 1 to 5, the multiplier key bank designated generally by the numeral ll (Fig. 1) is represented schematically by a coordinate group of lines. The vertical lines or columns from right to left denote units (U), tens (T), and hundreds (H), and the nine rows of horizontal lines denoting'the digits 1 to 9 inclusive, from bottom to top of the group.- Each intersection oi. the lines represents an electrical contact normally open, which may be closed upon the actuation of any suitable locking key or elec-' trical switch such as; for example, are described and shown in the patent to A. D. Hares-n, 1,378,- 950, issued May 24, 1921.

The multiplieand key bank is represented bytwo coordinate groups of lines II and I2. The vertical lines in each group from right to left denote units (U), tens (T), hundreds (H), tenhundreds (TH), and ten-thousands (TI), and the nine horizontal lines in each group denote the digits 1' to 9 consecutivelyfrom bottom to top. These two groups of lines represent two separate sets of' contacts, the closure 01' any set of which will be effected upon actuation of any key which the intersection of the lines represent; that is, for example, actuation of the nine key inthe tens (T) columnwillclosethecontacts represented by the intersection T-4 in both the group II and the group I2. As will become apparent as the description progresses, these groups of contacts I l and 42 control the units and the tens part, respectively, of the product ofthe multiplication of any digit y itself or any other digit.

Any particular problem may be set up on the banks In and lil2 by closing the contacts associated with the digits which go to make up the problem at the points corresponding to the digits in the multiplicand and the multiplier. These contact closures complete electrical circuits through a multiply commutator designated generally by the numeral Ii and send electric currents to distributor switcha designated generally by the numerals it and I1, 'whichin turn direct the currents to accumulators designated generally by the numerals I8 and ",io'r properly, registering or accumulating the results.

The multiplying commutator l comprises an electrical multiplication table in which there are seventeen sets, designated as 2l, of electrical contact disks. the 'nine sets shown on Fig; 1 representingtheunitspartoitheproductofany digit by any other digit and the ei ht sets shown on Fig. 4 representing the tens part of the prodnet of any digit by any other digit. The sets 2| representing the imits part 01' the product of 1, 2, 3, 4, 6, 7, 8, and 9 by any digit comprise three contact disks 2|, and the sets 2| representing the units part of the product of 5 by any digit and the tens par!- of the product of 2, 3, and 4 by any digit comprise two contact disks 2!. The sets 2| representing the tens part of the product of 5, 6, 7, 8, and 9 by any digit comprise three contact disks 2i.- These disks are all of a similar construction, the only variants being that the position of conducting elements thereon varies as the value of the partial product of each disk varies.

The left hand disk (Figs. 1 and 6) associated with the horizontal line representing the. digits 1 of the mulfiplicand bank ii has been selected for illusin-ation and will now be described in detail. Referring now to Figs. 6, 7, and 8, the contact disks comprise a disk 22 of insulating material mounted on and rotatable with a common shaft 25 which is contantly rotated at a uniformspeed. Secured to, one side of-the disk 22 is a metal plate 25, held in place by rivets 2'! which extend through the disk 22 and a second metal plate 28 to hold the plates 28 and 28 in a predetermined position on the disk- 22 and to electrically interconnect them. The plate 26 is so formed that, of a pair of brushes 29 and 30 associated therewith, the brush .2! always makes contact with the plate 2 andthe brush it makes contact at a predetermined point in the rotation of the disk and fora predetermined period sufficient to send an electrical impulse transmitted to the'plate 26 by the brush 29, out through the brush II' at the time of contact between the brush-ll and a portion ii of the plate 26. The' plate 22 is electrically connected through the rivets 21 with the-plate 26, and the brush 29, being constantly in contact with the plate 28, will supply electrical energy to the plate 28 whenever the brush 2! is connected in circuit with a source of elech-ical energy. When the. brush 29 is so supplied the plate-28 will also be supplied with electrical energy and since it has two contacting portions 3| and 32 adapted to engage a pair of brushes 35 and It at predetermined'intervals, the brushes will be supplied with electrical energy at predetermined intervals during the rotation of the disk 2|. The left hand disk 2| in eachset 2| has its lower left hand brush always in contact with a conducting portion thereof and the second and third disks from the left of each set are interconnected with the left them. Thus the lower left hand brush 2! connects the contacting portions of the disks in each set with the horimntal lines in the multiplicand banks I] and I2. Echo! the sets 2. is insulated from every other set, the conducting portions of the contact disks are insulated from the shaft 25 and the sleeves" are separated from the shaft 25 by insulating washers.

Fig. 6, the enlarged fragmentary schematic of the multiplying commutator, shows the arrangement of the mutiplieation table for two of the sets 2. representing the units part of the prodnets of the digits 1 and II. The multiplication table, as illustrated, follows the series of 1x1,

' hand disk by metal sleeves 31 positioned between 1X2, 1X3, 1X ..1x5, 1X6, 1x7, 1x8, and 1x9;

2x1, 2x2, 2 3, 2x4, 2x6, 2x7,'2 8, and 2X9, wherein each of the contacting-Portions of the disks represents 'a particular partial product, the

numerals adjacent the brushes,representing the units parts of the foregoing multiplications. It will be noted that there are no contacting por tions provided for the units part of product of 2 5 since the units part of the product of 2x5 is zero and no circuit connections need be made to indi- The multiplication table 3 to 9 inclusive by any digit, the tens part of the i products being represented by similar contact disks. i 4

In addition to the contact disks heretofore described, the multiplying commutator has mounted thereon a set 33 of three control contact disks and a set 35 of three transfer contact disks, the function of which will become apparent as the description progresses.

For the sake of simplifying the description, that portion of the system which controls the units part of the partial products sought, in effecting the computation, will bedescribed first, then that portion of the system which controls'the tens part of the partial products will be described, and finally the transfer mechanism which transiers the partial products from the register asso ciated with the tens part of the products to the units part register. Referring now to Figs. 1, 2, and 3, closure of any contact in the multiplicand bank H will interconnect a conductor 38 associated with the horizontal line in which the contact is closed and a conductor 39 associated with the vertical line in which the contact is closed. Each of the conductors 38 connects the lower left hand brush 29 associated with a set 20 of con-.

tact disks representing the product of the digits 1 to 9 by any digit, to the corresponding horizontal line representing the digits 1 to 9 in the multiplicand bank I I and each of the conductors 39 connects one of the vertical lines representing the units (U), tens (T), hundreds (H), tenhundreds (TH), and ten-thousands (TT) part of the multiplicand in the banks ii to grounded "battery 50 (Fig. 2) through conductors ll and the windings of one of five holding relays (l2 which are associated with the units (U), tens (T) hundreds (H), ten-hundreds (TH), and tenthousands (TT) contacts of the multiplicand bank I! and to the normally open contacts 45 of a relay 36.

The closure of'any contact in the multiplier bank iii will condition a circuit from grounded battery t? (Fig. 1) through a conductor 18, winding of one of a plurality of multiplier relays 39, (Figs. 1 and 4), one of a plurality of conductors Eli, which connect the horizontal line in which the contact is closed with its associated multiplier relay lli, through the closed contact in the multiplier bank l9, one of a plurality of conductors 5! connected to the vertical lines in the multiplier bank l representing the units (U), tens (T), and hundreds (H) digit in which the contact has been closed to one of contacts 52, 55 or 56 on an arcuate bank of contacts 51, forming a part of the dis-' tributor l6. These conditioned circuits will be completed to ground from the distributor IS in a manner to be described in detail hereinafter. This condition applies for the horizontal lines in the multiplier bank it which-are associated with the digits 2 to 9 inclusive, but does not apply for the horizontal line associated with the digit 1 to which is connected a conductor 58 which runs directlyto the upperleft hand brush of the left hand disk of each set 20. In like manner a conductor 59 connects the horizontal line in the multiplier bank i9 associated with the digit 9- directly to the upper left hand brushof the right hand disk ll of each set in the units part of the multiplying commutator.

After the keys controlling the multiplicand leading to one end of the winding of a locking relay $5, hereinafter termed the starting relay, and to a stationary contact 66 thereof. The other end of the winding of the starting relay 65 is connected to ground at 61 and the relay will be energized upon actuation of the starting key 60, attracting its armature 68 thereby to complete a circuit from ground 61 through the winding of the relay 65, stationary contact 66, armature 68, a conductor 69 connected thereto, and from the conductor 69 through a conductor ill to one end of the winding of an electromagnet II, the other end of which winding is connected to grounded battery at 12. It will thus be apparent that upon actuation of the start key 60 a circuit will be completed for maintaining the relay 65 energized until a circuit, to be described hereinafter, is completed to deenergize it. The electromagnet ll requires more current to operate it than does the relay 65 and the electromagnet will not be operated at this time but the means for operating it will be described hereinafter.

The electromagnet ll forms a part of the distributor switches l6 and H, and upon energization and release will rotate a shaft 15 common to both distributors, one step for each energization to bring brushes '16 to 81 inclusive into contact with successive contacts on arcuate banks of contacts 88 to 92 inclusive, 51 and 95 to I00 inclusive, respectively. The brushes 16 to 80 inclusive have connected thereto conductors Illl to Hi inclusive which, upon energization of the relay d6, will be connected through the contacts 35 of the relay i6 to conductors 39 which are associated with the ten-thousands (TT), ten-hundreds (TI-I) hundreds (H), tens (T), and units (U) rows of digits in the multiplicand bank ll respectively. The first time, in each cycle of operation of the distributor switch it, that the electromagnet H is energized, it will rotate the shaft l5 and move each of the brushes 76 to 8| off the first contact in each arcuate bank, which first contact is a dead contact, and into engagement with the second contact I of the banks.

The time of energization of the relay 46 (Fig. 2)

is controlled by contact disks l0? and. )8 (Fig. 1).

of the set 33 of three control contact disks. The contact disk ms is adapted fora predetermined portion of each revolution of the multiplying commutator shaft,,25 to connect ground at I09 through a normally closed contact M9 of a zero return key designated ill, conductors H5 and M6, the right hand movable contact ill of the starting relay 65 (which it will be assumed, has been energized) conductor H8, a brush I I9 which constantly engages the conducting portion of the disk E08, through the conducting portion of the disk to a brush E20. The brush I28 is connected through a conductor Hi to one end of a winding of a control relay H22 which will be energized for that portion of each revolution of the commutator shaft, during which the circuit is completed through the contact disk )8, since the other end of this winding of the relay is connected through a conductor l25,'and a normally closed contact l26 of a release relay I21 connected to grounded battery at 528. Upon being energized, the control relay lZZ will attract its armatures E29 and I39 to connect conductors lSi and E32 to con-.

ductors l35 and i0, respectively. The conductors conducting portion thereof, and connected to grounded battery I39 by a conductor I40. With the above described circuit connections in mind, it will be aparent that for a predetermined portion of each revolution of the multiplying commutator shaft 25 (assuming that the start key 60 has been operated) ground will be connected through the control. contact disk I01, brush I36, conductors I3I and I35 to a conductor I4I connected to one side of the winding of the relay 46 which will thereupon be energized since the other side of its winding is connected to grounded battery,I42 (Fig. 2).

The electromagnet 1i will be energized once for each revolution of the commutator shaft 25 under control of the control contact disks M11 and I08 by the contact disk I01 connecting ground at I39 through the brush I31, conductors I32 and 10, and will advance the brushes 16 to 81 inclusive into engagement with successive contacts in their associated arcuate banks of contacts in the distributor switches I6 and I1 each time it is energized. Assuming that the relay 46 has been energized as described hereinbefore, the first time the electromagnet H is energized, it will connect the vertical rows of contacts in the multiplicand bank II associatedwith the units (U), tens (T), hundreds (H), ten-hundredths (TH) and tenthousands (TT) digits through the conductors 39 associated therewith the conductors I05, I04,

I03, I02, and IM to conductors I45, I46, I41,-

brushes 80, 19, 18, 11 and 16 will be moved into engagement with contacts on the arcuate banks connected to conductors I41, I48, I49, I50, and I5I. The fourth and fifth times the brushes are advanced, they will engage contacts to which no conductors are connected and the sixth to tenth times, the eleventh to fifteenth times and sixteenth to twentieth times thebrushes are advanced, the connections made in the first to fifth moves will be repeated. The conductors I45 and I5I inclusive are connected to one side of the windings of electromagnets I55 to I6I inclusive, respectively. The other side of the windings of the electromagnets I 55 to "H are connected through a conductor I12 to grounded battery at I15 and the electromagnets will be energized when ground is connected thereto. When energized, the electromagnets I55 to I6I serve to connect brushes I65 to I'll, respectively, to acommon shaft I12, which is rotated constantly in synchronism with the shaft 25, and to rotate the brushes for the duration of the energization of the associated electromagnet. Rotatable with each of the brushes I65 to "I is a contact disk I13, the purpose of which-will become apparent as the description progresses. The movement of the brushes I65 to "I is therefore controlled by the electromagnets I 55 to I6l and the length of time that any of the electromagnets I55 to I6I is energized, will determine the amount of rotation of its associated brush I65 to "I. The accumulator switch I8 serves as a register to indicate the result of a computation and readings may be taken therefrom in terms of the position of the brushes I65 to I1I on the arcuate banks of ten contacts each, associated wtih the brushes or suitably numbered dials (not shown) might be provided to assist in reading the result.

If it is desired to permanently record the result of the computation, the result may be transmitted from the accumulator switch through a plurality of output cables I16, each of which comprises ten leads connected to individual contacts on the arcuate bank associated with the brushes I65-to I1I, inclusive. Any suitable type of electrically operated recording mechanism may be used for this purpose, it being necessary only to make the recording mechanism operable when ground is supplied thereto since the brushes I65 to I'll are normally connected to ground. A type of recording mechanism which would be particularly adapted for usein making permanent -records of the results of computations performed by applicant's apparatus is disclosed in the duplicating apparatus forming the subject matter of Patent No. 1,881,631, issued on October 11, 1932, to H. G. J ohnstone. Ground is normally supplied to the brushes I65 to I'll from a conductor I11, connected to a conductor I18,'which is connected through the lead I I5 and the zero return key III in its normal-position (Fig. 1) to ground at I09.

The step by step rotation of the shaft 15 of the distributor switch I6 not only advances the brushes 16 to 00 a step at a time to cause them to engage successive contacts in their associated banks of contacts, but also imparts a step by step rotary motion to the brush 8I associated with the arcuate bank of contacts 51. The first time in each half revolution of the shaft I5 that the magnet H is actuated, the brush 8| will be moved from the first or dead contact of the bank 51 into association with contact 52 tothereby complete a circuit from ground at I39 (Fig. 1) through the conductor I40, contact disk I01, brush I36, conductor it, closed contact I29, conductors I35 and HI to a conductor I19, connected to .thebrush 8I'and through the brush 8| to contact 52, the conductor 5! associated with the vertical line representing the units part of the multiplier in the multiplier key" bank I0, thence through any closed contact in the multiplier key bank I0, one of the conductors 50, 58 or 59, associated therewith to one end of the winding of one of the relays 49 and from the other end of the winding on one ofthe relays 49 through the conductor 48 to grounded battery at 41. The second time the electromagne't 'II is energized, it will advance or step the brush 8| into engagement with the contact 55, connected by one of the conductors 5I to the tens row of contacts in the multiplier bank I0, and the third time the electromagnet 1| is energized it will interconnect the brush 8I with the line representing the hundreds digits in the multiplierbank I0. The time of actuation of the electromagnet H is so controlled,that a partial product of the digits set up in the multiplicand bank II by the units digit set up in the multiplier bank I0 will be transmitted to-the accumulator switch I8 and thereupon the electromagnet 1I will again be actuated to step the brushes 16 to 8I into engagement with the second contacts in their associated arcuate banks of contacts thereby associating the brushes 16 to '80 with the next higher' order of the register or accumulator I8 and moving the brush 8I into engagement with the contact on its associated bank 51 which connects ground through the tens column of the'multiplier bank I0 and as soon as the partial product of the digits set up in the multiplicand bank It by the digit set up 2,225,410 in the tens row of the multiplier bank I has been transmitted to the accumulator switches, the electromagnet 1I will be again actuated to connect ground through the hundreds column in the multiplier bank. After the brush 8| has been successively associated with the contacts 52, 55, and 56, it will, upon the next actuation of the electromagnet H, be moved into association with the next successive contact on the bank 51 to thereby connect ground from the brush 8| through a conductor I00 and a conductor I8I to actuate the transfer mechanism for transferring the tens part of the product of all of the digits of the multiplicand by each digit in the multiplier from the accumulator switch I9 into the accumulator switch I8, as will be described in detail hereafter. The next time the electromagnet H is energized, the brush 8I will engage the fifth live contact on the bank 51 to complete a circuit from ground through the brush 8 I, a conductor I82, con.- ductor I 85 to the windings of the release relay I21 which will thereupon be energized to attract its armature I26, breaking the circuit to the control relay I 22 which will release its armatures and break the circuits controlled by the control contact disks I01.

The circuit connections completed in the first five movements of the brush III will be duplicated in the sixth to tenth and eleventh to fifteenth movements of the brush, and the connections completed in the first four movements of the brush 9| will be duplicated in the sixteenth to nineteenth movements thereof, but the twentieth and twenty-first movements of the brush will connect ground through the brush, the-twentieth and twenty-first contacts of the bank 51, a conductor I90 and the normally closed contacts of the electromagnet H to one end of the winding thereof, the other end of which is connected to grounded battery 12, thereby operating the electromagnet 1| twice to advance the brushes 16 to 81 over the twentieth and twenty-first contacts on their associated banks without completing any other circuits than those just described, and stepping the brushes into engagement with the twentysecond contacts on their associated banks.

This variation in the advancement of the brushes is necessitated in order to use selector switches without modifying them since in telephone practice the selector switches used have twenty-two contacts in each arcuate bank. The brush 8| upon engaging the twenty-second contact on its associated bank 51 duplicates the connections made when the brushes engaged the fifth, tenth, and fifteenth contacts on the bank. From the foregoing, it will be apparent that for each half revolution of the shaft 15 supporting the brushes 16 to-81, four separate and distinct problems may be computed.

The accumulator switch I8 in receiving the partial products transmitted thereto from the multiplying commutator I5, may in the course of a particular problem, have partial products transmitted thereto which, when accumulated, will total more than 9, at which time it becomes necessary to haveany particular brush to which such products have been transmitted, pass from the position where it indicates 9, into the position where it will indicate zero, and it will also be necessary to add 1 to the next higher denominational register represented by one of the brushes I65 to I'll in the next higher denominational accumulator switch. In order to accomplish this operation, which will hereinafter be termed the carry, any form of carry mechanism may be used, but the following form has been selected because of its simplicity. An auxiliary contact I9I is provided on each of the arcuate banks of contacts associated with the brushes I66 to I1I, which is positioned between the contacts which represent 9 and zero. Any of the brushes, upon engaging the contact I9I, will complete a circuit from ground at I09 (Fig. 1) through the conductors II5, I18 and I11 through the contact I9I, a conductor I92 connected thereto to the winding of one of a plurality of carry relays I93 associated therewith and having the other side of its winding connected to grounded battery at I94 through a common conductor I95. The right hand contact I99 of each of the carry relays is connected to the conductor I92 and upon energization of its associated relay I93, will engage a contact 200 connected to a conductor 20I.

The conductor 20I is connected through a conductor 202 to a contact disk 205 forming a part of the set 33 of control contact disks and having the lower left hand brush associated therewith connected to ground at I39. The conducting portion on the disk 205 associated with the lower right hand brush is such that ground will be connected therethrough to complete a circuit for holding operated any carry relay which received an energizing impulse from one of the brushes I 66 to I'll.

Any carry relay I93, upon being energized as described hereinbefore, will attract its contacts, the right hand contact completing the'locking circuit just described, and the left hand contact of the particular relay or relays I93 which have been energized will complete circuits from a com-- mon conductor 206, connected through a conductor 204 and the contact disk 205 to ground at I39; to conductors 201, and/or 208', and/or 209, and/or 2I0, and/or 2| I, and/or 2I2,'depending on the relay or relays which have been energized. The conductors 201 to 2I2 inclusive-are connected to the right hand movable and left hand stationary contacts (Fig. 3) of a carry con-.

trol relay 2I3, and the conductors 208 to 2I2 inclusive, are connected by conductors 2I6 to 220 inclusive, to brushes 2'2I to 225 inclusive, associated with the contact disks I13, which rotate with the brushes I61 to I1I, respectively, of the accumulator switch I8. The relay 2I3 has one side of its winding connected by conductors 228 and 229 to a brush 230 associated with the control contact disk 205, and has its other side connected by conductors 230 and 23I to a normally open contact 221 of control relay I22. However, the control. relay I22 is energized early in the cycle of operation of the circuit and will be held operated since its left hand front contact 226 connects ground through the relay to grounded battery at I28 until the release relay I21 is operated, and since the relay I22 is locked in its operated position, grounded battery at I28 will be connected through the right hand front contact thereof to the conductor 23I.

At a predetermined point early in the cycle of rotation of the commutator shaft, the contact disk 205 will connect its brush 230 to ground at I39, thereby to energize the relay 2I3, and hold it operated for practically the entire cycle. The right hand stationary and left hand movable contacts of the relay 2 I3 are connected through conductors'232, 233, 234, 235, 236, and 231 to the electromagnets- I51, I58, I59, I60, I51, and an electrom'agnet 242 respectively. The electromagnet 242 controls the operation of a brush 243 in I the same manner that the electromagnets I55 to I6I control the brushes I65 to III respectively, and the brush 243 in engaging its'associated contacts may be utilized to actuatea recording de- 5 vice through one of the cables I16 in the same manner as the brushes I65 to I1I.

Upon energization of anyof the relays I93, they will condition for operation circuits running from grounded battery at I15 (Fig. 2) through the electromagnets I55 to I6I and 242 which are associated with the particular relays I93 which have been energized, through the closed contacts of the carry control relay 2I3, to the left hand movable contacts of the relays I93 and from the left hand stationary contacts of the relays I93, conductors 206 and 204 to the upperright hand brush associated with the contact disk 205. The cutting of the conducting portion of the contact disk 205 associated with the upper right hand brush is such that at a point in the cycle of rotation of the commutator shaft at which the par tial product of the digits of the multiplicand by one digit of the multiplier has been transmitted to the accumulator switch I8, contact will be made between the brush and the conducting portion to connect ground to the hereinbefore described conditioned circuit long enough to energize the relays I 55 to I6I and 242 which have been conditioned for operation, a length of time sufiicient to move their associated brushes to the point where they will add one to the registered partial products.

The carry circuit just described will function for the majority of cases, but obviously it alone would not operate to give the correct result if there were a multiple carry to be executed; that is, ii for example, the brushes I61 and I68 were both resting on theninthcontact of their respective banks and the brush I66 passed from the ninth contact to the zero contact, thereby making a carry necessary. Therefore, there has been provided circuit connections for effecting a multiple carry which will now be described. It will be apparent that no multiple carry circuit connections are necessary for the banks of contacts representing units and tens, and controlled by the brushes I65 and I66 respectively, since in any problem of multiplication the units parts 01 the result never has additional digits added thereto during the process of multiplication and therefore the units and tens are not provided with multiple carry circuit connections. However, since it is possible to have nine or less registered in the tens part of the accumulator switch, and in a given problem one or more up to nine may be added to the digit registered in that part of the switch, each of the conductors 232 to 231 inclusive has a brush 2 connected thereto which engages the contact disk I13 associated withthe electromagnets I51 to I6I and 242, which brushes 2 always make contact with a conducting portionof the disks I13. The addition of these circuit connections will simultaneously add one to all of the, denominational registers in the accumulator switch I8 which are conditionedfor operation through the ordinary carry connections or in the event that there is a multiple carry to be efiected. The brushes 22I, 222, 223, 224, and 225 engage the conducting'portion of the contact disks I13 only whentheir associateddenominational registers in the accumulator switch indicate 9. In the event that adjoining registers are to pass from -9 to zero in the eflecting of a computation, the following circuit connections digits times one. multiplicand bank I2 associated with the digits brushes I 66, I 61, and I68 are resting on the ninth contact of their associated banks and that the digit 3 is added to the: denominational register associated with the brush I66. The brush I66 will pass from engagement with the ninth contact into engagement with the second contact of its associated bank, and in so doing will pass over the auxiliary contact I9I associated therewith. Since the brush I66 is connected to ground at this time as described hereinbefore, it will, in passing over the contact I9I complete a circuit from ground through the conductor I92, the associated relay I93, conductor I95 to groundedbattery at I94, energizing the relay I93 which will, as pointed out hereinbefore, remain locked in its operated position. Simultaneously with the operation of the relay I93, circuits will be conditioned from the upper right hand brush associated with the contact disk 205 through conductor 204, left hand contact of the relay I93, conductor 201, contacts of the energized carry control relay 2I3, conductor 232, brush 2, brush 22I engaging the conducting .portion of the contact disk I13, conductors '2I6 and 208, contacts of the energized carry control relay 2I3,- conductor 233, its associated brush 2, contact disk I13, bmsh 222, conductors 2H and 209, contact of the energized carry control relay 2I3, conductor 234, to the winding of the electromagnet I59. Now since the control contact disk 205 will supply ground from I39 through its upper right hand brush, conductor 204, conductor 206, to the left hand contact of the relays I93 which have been energized through the disks I13 through the conductors 232, 233, and 234 to energize the electromagnets I51, I58, and I59 for the purpose of stepping brushes I61, I68, and I69 ahead one contact, the denominational registers in the accumulator switch I 8 representing tens (T), hundreds (H), ten-hundreds (TH), and ten-thousands ('I'I) will register 2 0 0 1, respectively.

From the foregoing description, itis believed that it will be apparent that the units part of the products of all of the digits in the multiplicand by all the digits in the multiplier in any particular problem will be indicated upon the accumulator switch I8 due to the completion of the hereinbefore described circuits. Referring now to that portionoi' the multiplying commutator which controls the tens part of the partial products or any selected problem, as shown in Fig. 4, it comprises-the hereinbefore described sets 20 ofcontact disks 2|, all at which are operable in exactly the same manner as were the disks associated with the units part of the problem and it will also be apparent that the accumulator switch I9 will have transmitted thereto the results of the tens part of the computation which will be directed to the accumulator switch I9 through the selector switch I1.

In the part of the mechanism which computes the tens part of the productof the digits 0! the multiplicand by the digits of the multiplier, it will be noted that the horizontal line associated with the digit 1 is not connected in circuit with any part of the multiplying commutator I5 since there will be no tens part or the product of any The horizontal lines of the 2, 3, 4, 5, 6, 7, 8, and 9, are connected through conductors 250 to the lower left hand brushes of the sets 20 of contact disks 2| associated with the digits 2, 3, 4, 5, 6, '7, and 9, and the vertical linesassociated with the units (U), tens (T),

y will be completed; for example, assume that the hundreds (H), ten-hundreds (TH), and tenthousands ('IT), denominational digits of the bank I2 are connected through conductors 25!,

252; 253,. 254, and 255 to holding relays 259, 260,

26!, 262, and 263, respectively, in the same manner that the conductors 39 and 4! connect the vertical lines of the multiplicand bank I! to the holding relays 42 associated therewith and theconductors 25! to 255 are connected'to the movable contacts of a relay 261, the purpose of which is the same as the relay 46 in that portion of the mechanism assigned to the units part of the products. The brushes 82 to 86 in the distributor switch I1 complete connections through their associated banks 95 to 99 in the same manher as do the brushes 16 to 80, described herein-. before in connection with the units part of the problem and will actuate electromagnets 268, 269, 210, 21!, 212, 213, and 214 for controlling the operation of brushes 218, 219, 280, 28!, 282, 283, and 284, in the accumulator I9 for registering the tens (T) to ten-millions (TM) denominations in the tens part of the products. The brushes 218 to 284 have contact disks 28,8 associated therewith, similar to the contact disks I13, and which perform the same function in the tens part of the problem that the disks I13 perform in the units part, and auxiliary contacts 289, similar to the auxiliary contacts I9I. Carry relays 290 and 29! similar to the carry relays I93 and 2I3, cooperating with the electromagnets 268 to 214 and the contact disks 288 effect a carry and/or a multiple carry where necessary in the tens part of the partial products. Since the circuit connections effected in computing the tens part of a particular problem are similar to those described hereinbefore in connection with the units part of a problem, the foregoing brief description of the analogy therebetween will, it is believed, obviate the necessity of further describstepped into engagement with the fourth contact on the bank E00 and will connect ground at 294 through the fourth contact, conductors 295 and 296, to the lower left hand brush 291 associated with the set 34 of transfer contact disks. The set 34 of transfer contact disks are similar in construction to the other contact disks and have conducting portions thereon which representthe digits 1, 2, 3, 4, 5, 6, 7, 8, and-9, respectively, from left to right (Fig. 4) and are connected through conductors 238, 299, 300, 30!, 302, 303, 384, 305, and 306 to the first to ninth contacts on each of the arcuate banks of contacts in the accumulator switch I9, respectively, and will connect ground through brushes 218, 219, .280, 28!, 282, 283, and 284 to the contacts of a pairvof transfer relays 3I0 and 3! I. One end of each of the windings of the relays 3I0 and 3!! is connected to grounded battery at.3!2 through a common conductor 3 I3 and the other end of each of the winding of these relays is connected through conductors I8! and I to the fourth contact on the arcuate bank of contacts 51 forming apart -of the distributor switch I6 and since all of the brushes of the distributor switch are advanced from contact to contact in unison and the brush 8! is connected to ground, upon closure of the circuit through brush I36 on contact disk I01 the transfer relays 3I0 and 3!! will be energized to attract their movable contacts completing circuits from the brushes 218 to 284 through conductors 3I4, 3I5, 3I6, 3I1, 3I8, 3I9, and 320, respectively, to one side of the winding of transfer help relays 324, 325, 326, 321, 328, 329, and 330, respectively. The other side of the windings of the transfer help relays are connected through a common conductor 33! to the left handback contact" of transfer relay 3! 0 and through the left hand backcontact to grounded battery at (H2. The completion of circuits to anyof the transfer help relays 324 to 330 will energize them and cause them to attract their armatures to hold them operated since their armatures are connected by a common conductor 332 to ground at 333. Ground at 333.will also be connected through the armatures of the energized relays 324 to 330 to one side-of the windings of predetermined ones of the electromagnets I56 to I6! and/or 242, dependent upon which of the relays 324' to 330 are energized and the ground connection to the electromagnets I56 to I6!, and

242 will be maintained until relays 3!!! and 3!! are deenergized due to the removal of the ground connection therefrom. Since ground is connected to the transfer relays 3I0 and 3Il through the bank 51 of the distributor switch I6, conductors I19, I4I, I35, and I3! and the contact disk I01.

the relays 3! 0 and 3!! and such of the relays 324 to 330, and'electromagnets I56 to I6! and 242 as had been energized will be simultaneously released under control of the contact disk I01.

It should be noted that the differential timed impulses impressed upon the conductors 298 to 306 by the set 34 of transfer contact disks are selected in accordance with the position of the brushes 82 to 86 and will control the transfer of the number registered on the tens accumulating register I9 from that register to the units accumulating register I8.

Just subsequent to the release of the transfer 'relays 3I0 and 3!! the electromagnet 1! will be energized and released to step the brushes 16 to 81 into engagement with the fifth contact on their associated banks and operate the release relay I21 to stop the operation of the circuits. At this time the accumulator switch I8 will have registered therein the final result of the problem and the permanent record may be made therefrom as pointed out hereinbefore.

After a reading has been taken from the accumulator switch I8 or a record made therefrom, the mechanism may be set to zero or normal by the completion of the following circuits: The zero return key I I! may be operated manually to disconnect ground from its contact I I 0 and connect it to a contact 340 connected through a conduc tor 34!, (Figs-1, 4, 3, and 5) to one side of the windings of zero return relays 342, 343, and 344. The other side of the windings of the relays 342,

343, and 344 are connected through a conductor 345 to grounded battery 346 (Fig. 3) and the relays will be energized to attract their movable armatures upon such operation'of the zero return key III. The movable contacts of the zero re- .turn relays 342, 343, and 344 are connected to ground at 350, 35! and 352, respectively, and upon actuationwill connect ground through conductors 353 to 361 to the upper left hand brush associated with the'contact disks 288 and I13 rotatable with the brushes 218 to 284, I65 to I1! and 243, respectively, which indicate the tens (T), hundreds (H), ten-hundreds, (TH), ten-thousands (TT), hundred-thousands (HT), millions (M), and ten-millions (TM) denomination representing the tens part of the product and the units (U), tens (T), hundreds (H), ten-hundreds (TH), ten-thousands (T'l), hundred-thousands (HT), millions (M), and ten-millions-(TM) denominations, representing the units part of the 10 product.

The upper left hand brush associated with the contact disks 288 and. I13 makes contact therethrough at all times except when the brushes of the accumulator switches I8 and I9 rest on zero hand brush acircuit will be completed through the contact disk or disks to the lower left hand brush associated therewith, the windings of one or more ofthe electromagnets I55 to I6I in- 20 clusive,.242 and 268 to 214, inclusive, the conductor I12 to grounded battery at I15 to thereby rotate the brushes of the accumulator switches to their zero position whereupon the contact disks will break the circuit, leaving the accumulators 25 in their normal position registering zero.

A better understanding-of the mechanism will be had by referring to the following description of the operation thereof wherein the connections completed in computing a particular problem will H be described briefly. Assume that it is desired to multiply the number 20468 by the number 359,

and that the accumulator switches I8 and I9 are in their normal position registering zero. The number 20468 may be set up in the multiplicand .3 banks II and I2 by actuating the keys represented by the horizontal lines 2, 4, 6, and 8 in the vertical columns assigned to the ten-thousands (T'I), hundreds (H), tens (T), and units (U), as indicated by the circles at the intersection of 40 these lines. It will be noted that no key has been depressed in the vertical column representing the ten-hundreds (TH) denomination of the multiplicand. The purpose of this will become apparent as the description progresses. The number 45 359 may be set up in the multiplier bank I0 by closing the contacts in the positions indicated by the circles in the hundreds (H), tens (T), and units (U) vertical lines of the multiplier bank I0.

After the problem has been set up on the multi- 50 plier bank I0 and multiplicand banks II and I2, the start key 60 may be depressed, momentarily completing the circuit to the starting relay 65, causing it to attract its armatures and connect ground 61 through its winding, contact 68, con- 55 ductors 69 and 10, to the winding of the distributor switch electromagnet 1| and grounded battery at 12, thereby locking the starting relay 65 in its operated position. Upon operation of the relay 65 a circuit will be completed from 60 ground at I09 through the contact IIO, conductors I I and I I6, contact II1 of the starting relay 65, conductor I I8, to brush I I9 and as the contact disk I08 reaches a predetermined point in its rotation (it being constantly rotated with the shaft 25), through the contact disk I08 of the set 33 of control contact disks, conductor I2I to control relay I22 through the left hand winding of the control relay, a conductor I25, normally closed contact I26 of release relay I21 to grounded batftery at I28 thereby energizing the control relay I22 and causing it to attract its contacts. Upon attraction of the contacts of the relay I22, its contact I30 will be connected to the conductor and, upon rotation of the commutator shaft 25, (5 will connect ground at I39 through the brush 1.) and upon ground being supplied to the upper left- .contact I26 of the release relay I21 to grounded battery at I28.

Simultaneously with the release of the start .ing'relay 65 the brush I31-will connect ground at I39 through the contact disk I01, conductors I32 7 and 10, the winding of the electromagnet H to grounded battery at 12 energizing the electromagnet momentarily and then releasing it to step the brushes 16 to 01 into engagement with the first contact on their associated banks.

Just subsequent to the completion of the movement of the brushes 16 .to 81 into engagement with the first contacts on their associated banks, and for substantially the remainder of the rota- 5 tion of the contact disk I01, the control relay I22 having been locked in its operated position, the control contact disk I01 will connect ground at I39 through the conductor I40, brush I36, conductors I3I, I35, I4I, windings of the relays 46 and 261 to grounded battery at I42 and at the relay 261 energizing .the relays 46 and r 261. Ground will also be connected from the conductor I4I through the conductor I19, brush 8I, contact 52 of the bank 51, conductor 5| to the closed 35 contact'at 9 in the units (U) column of the multiplier bank I0, conductor 59 to the brushes associated with the contact disks in the units part of k the multiplying commutator representing the digit 9 times itself and every other digit. except 5,

and through the conductor I50 associated with the horizontal row representing the digit 9 in the multiplier bank to the winding of the relay 49 representing the multiplier digit' 9 through conductor 48 to grounded battery at 41 to energize 45 the relay 49 representing the digit 9 of the multilier. p The relay 49, upon beingenergized will attract its contacts which are connected to. ground thereby to supply ground to the brushes associated 50 with the contact disks representing the multiplier digit 9 in that portion of the multiplying commutator which controls the tens part of the product and to the brush associated with the contact disk representing the product of multiplier digit 9 times the multiplicand digit 5 in that portion of the multiplying commutator I5 representing the units part of the product. In this manner all of the brushes amociated withthe contact disks in the multiplying commutator I5 0 representing the multiplier digit ,9 have ground banks II and I2 which represent 8 in the units column, 6 in the tens column, 4 in the hundreds 25 tion of the control contact disk I01.

column, and 2 in the ten-thousands column, and simultaneously through the conductors 39 and 25I, 252, 253, and 255 through the closed contacts of the relays 46 and 261 to the brushes 16, 18, ,19, 80, 82, 84, 85, and 86 in the distributor switches I6 and I1. This ground connection is made only momentarily by the conducting portions of the contact disks, but will complete circuit connections to the windings of the holding relays 42, 259, 260, 26I, and 263; and since thev other side of the windings of the holding relays are connected to grounded battery, they will be locked in their operated position until their connection to ground is broken through the opera- Simultaneously-with the release of the holding relays,

the relays 46, 49 and 261 will be released since they alsoreceive their ground from the control contact disk I01 through the brush I31. While locked in their operated position, the holding relays will connect ground under the control of the control contact disk I01 through their contacts to the conductors 39, 25I, 252, 253, and 255 to the brushes 18, 18, 19, 80, 82, 84, 85, and 88,

carries necessary, the energization of the carry control relays is of no import.

Shortly after'the release of the holding relays under control of the control contact disk I01 through its left hand brush I36, ground will be connected momentarily through the control contact disk I01, right hand brush I31, conductors I32 and 10 through the winding of the electromagnet 1| to grounded battery at 12, thereby to energize and release the electromagnet 1| to step l the brushes 16 to 81 into engagement with the second contact on their associated arcuate banks of contacts. At this time the accumulator switches I8 and I9 have registered therein the units and tens parts, respectively, of the product of 20468 9, and a reading thereof would be as in the distributor switches I6 and I1. follows:

Accumulator switch 18 Accumulator switch 19 TMMHTTTTHH'IUTMMHT'TTTHHT To0so64200r 0357 In summing up, it will be apparent that since the holding relays are energized one at a time, depending upon the quantitive value of the digit to be sent from the multiplying commutator,

. value of the digit to be indicated in the accumulator switches. In the particular problem selected for illustration, the holding relays 42 associated with the units (U), tens (T) hundreds (H), and ten-thousands (TT) lines in the bank I I, will be energized for lengths of time suflicient to transmit 2, 4, 6, and 8 to the accumulator banks of contacts representing units (U), tens (T), hundreds '(H), and ten-thousands (TD in the accumulator switch I8, and the holding relays 259, 260, 26I, and 263 will connect ground through the brushes 86, 85, 84, and 82, respectively, for lengths oftime sufilcient to transmit '7, 5, 3, and l, to the tens (T), hundreds H), tenhundreds (TH), and hundred-thousands (I-IT) banks of the accumulator switch I9. This is accomplished by the brushes 80, 19, 18, and 16 connecting ground to one side of the windings of the electromagnets I55, I56, I51, and I59, and

the brushes 86, 85, 84, and 82, connecting ground for a length of time sufiicient to advance them into engagement with their second, fourth, sixth, eighths. s venth, fifth, third, 'and'first contacts respectively. I

' In eachrevolution of themultiplying commu "ta tor, subsequent to the timewhen any of the accumulator switches I8 or 'I91have completed their registering operation, the following circuit The brush 8| of the distributor switch I6, upon engaging its second contact 55, will connect ground at I39 through the control contact disk I01, brush I36, conductors I3I and I35, conductor I4I to again energize the relays 46 and 261, through'the conductor I19, brush 8|, contact 55; the conductor 5| associated with the vertical line representing the tens (T) denominational column of the multiplier bank I0 through the closed contact 5 ,to the relays 49 associated with the digit 5 of the multiplier, through the windings of the relays to grounded battery at 41, thereby energizing the relays 49 associated with the digit 5 of the multiplier to connect ground through the multiplying commutator and at predetermined intervals through the conductors 38 and 250 to the closed contacts in the multiplicand banks II and I2, the conductors-39 and 25I to 255 to the contacts of the relays 46 and 261. The relays 46 and 261, having been energized, ground will be connected through their contacts to the brushes 82 to 86 at predetermined intervals primarily under control of the contact disks 2I'associated with the multiplier digit 5 and maintained thereon through the holding relays 259 to, 263 which were alsoenergized under control of the same contact disks 2| in the multiplying commutator I5 and locked in operated position under control of the control contact disk I01."

tance sufficient to add 4,, 3, 2, -and '1 thereto,

respectively. It'Will be noted at this time that no circuits were completed in the units part of the problem for advancingthjbrushes of the accumulator switch I8. "This conditionis due to the fact that in the particularproblem selected, namely 20468X'359'the units part Of the partial product of 5X20468 is 0,0, and since the brushes of the accumulator switch I8 need not be advanced, the circuit connections necesbrush 216 'is on the seventh contact, brush 219 is on the ninth contact, brush260 is on the sixth contact, brush 26I is on the second contact, brushes 282 and 266 are on the first contacts and brush 2841s on the zero contact 01'' their respective At this time the electromagnet H is energized momentarily as described hereinbefore to step the brushes of the distributor switches I6 and I1 into engagement with the third coutacts on theirre'spective banks of contacts.

As described hereinbefore in connection with the multiplicationof 20468 by the digit 9, a carry circuit is energized early in the ,cycle of operation energized.

of the multiplying commutator; however, the carry is again of no import, since none of the brushes in the accumulator switches have passed from the position where they indicate 9 to a position where they would indicate zero. Just after the electromagnet 1I operates to advance the brushes oi the distributor switches I8 and I1 into engagement with the third contacts. of their associated banks the relays 48 and 261 will be On engaging its third contact, the brush 6| will connect ground through the contact 66, conductor 6| associated with the vertical line representing the hundreds denomination in the multiplier bank I6, the conductor 60 associated with the digit 3 horizontal line of the multiplier bank I6, to the relay 49 associated with the digit 3 of the multiplier, through the winding of this relay 66 to grounded battery at 41, thereby to ener-. gize the-relay 46 associated. with the digit 3 the multiplier-and connect ground through its contacts to the brushes associated with the contact disks 2| or the sets 26 in the multiplying commutator which represent the product of any digits by 3. At predetermined times in the cycle of rotation of the multiplying commutator, the contact disks 2| will connect ground through the lower left hand brushes of each set 20,'conductors 66 and 266 to the horizontal lines representing the digits 2, 4, 6, and 8 in the multiplicand banks II and I2 though the closed contacts indicated by the circles. conductors 26, 26I, 262,

266, and 266 to the holding relays 42 and 269,

260, 26I, and 266 and through the contacts'of the relays46 and 261 to the brushes 62, 84, 86, 86, 16, 16, 16, and; 66. Ground, will thus be connected under control of the control contact disk I61 through the brushes 62, 64, 66, 66, 16, 16, 19', and 66, to the electromagnets 212, 21I, 210, I6I, I66, I66, and I61 to advance the brushes 262, 26I, 266, Ill, I66, I66, and I61, 1, 1, 2, 6, 2, 8, and

4 contacts, respectively. At this time, the brushes 218,219, 26., "I, and 263 will be resting upon their seventh, ninth, eighth, third, second, and first contacts respectively, and the brushes I66, I66, I61, I66, I68, I'll, and I'll will be resting on their second, fourth, zero, eighth, zero, first, and

sixth contacts, respectively. Simultaneously with the release of the electromagnets I61, I66, etc.,

the control contact disk I01 will also release the relays 46, 49, and 261; I

The brushes I61 and I69, it will be noted, have passed from the position where theyindicate 9 in the position where they indicate zero, and therefore a carry of 1 to the next higher denomination must be eilected. As pointed out hereinbefore, the carry relays 2 I6 and 29I are actuated early in the cycle of rotation of the multiplying commutator I6, thereby attracting the movable contacts andconditioning the carry circuits as described hereinbefore for actuation. Brushes I61 and I 60 in passing over the auxiliary contacts I9I connect ground under control of the control contact disk I01 and brush I31 through the conductors I92 to the relays I98 associated with the brushes I61 and I69. The other end of the winding of the relays I93 are connected to grounded battery at I94 and upon actuation .0! the relays I98 associated with the brushes I61 and I69 they will remain locked in their operated position since their right hand contacts are con nected through the conductors "I and 202 and the contact disk 206 to grounded battery at I69 for practically the entire cycle 01' rotation of the multiplying commutator. In attracting their left hand contacts, the relays I96 associated with brushes I61 and I69, will connect the conductors 208 and 2| 0 through the conductor 206 and 204 to the upper right hand brush of the control contact disk. 206 which once in each cycle oi. the multiplying commutator and just prior to the release of the relays 2|8 and 29I will connect ground to the conducting portion thereof to the conductors 204, 206, 206, 2", the contacts of the energized relay 2I6, conductors 266 and 236 to the winding of the electromagnets I66 and I60.

' The other side of the winding of the electromagwith which they are associated, so that with the accumulator switches I 6 and I6'at this point will register as indicated below:

Accumulator switch 18 Accumulator switch 19 HTTTTHHTUMH TTTTHHT As soon as'the accumulator switches register the above amounts, connection between the brush ,ss

266and the control contact disk 206 will be broken to release the carry holding relays 2I6 and 26f.

Immediately after the connection oi the ground which actuates the carry relays I62 has 00 performed its function, the control contact disk I61 will again connect ground to the electromagnet 1| to step the brushes of the distributor switches I6 and I1 into. engagement with the fourth contact on their associated banks andin 65 so doing ground will be connected through the brush I66 associated with the control contact disk I61, conductors I66 and I16,the fourth contact on the bank 61, conductors I66 and "I, to

the transfer relays 6| 6 and 6| I, energizing them 70 thereby to connect the brushes 216, 216, 266, 26I, 262, 266, and 264 of accumulator switch I6- through their associated contacts to the conductors 6I4, 6I6, 6I6, 6I1, 616, 6", and 826, con-q nected to the transfer help relays 624 to 666, re

spectively. The brush 81 of the distributor switch IT, in engaging its fourth contact, will connect ground at 294' through the conductors 295 and 296 to brush 29'! associated with the set which these brushes indicate as being registered The transfer conin the accumulator switch 19. tact disks of the set 34 are so formed that in each cycle of the multiplying commutator the brushes from right to left (Fig. 4) make contact momentarily and successively to connect ground through their associated conductors to the contacts of the accumulator switch l9. It will thus be apparent that assuming that the cycle of operation of the set 38 transfer contact disks is divided into nine units, in the first unit ground will be connected through the conductor 308,

'brush 215 engaging the ninth contact on the hundred bank of the accumulator switch 58, contacts of the transfer relay 3i i, conductor 3l5, winding of transfer help relay 3'25, conductor 33d, left hand back contact of the transfer relay 358 to grounded battery 3H2 thereby energizing the electromagnet i5? and the transfer help relay 325 which willlock in its operated position upon attracting its contact to connect ground therethrough and through the conductor it? to the electromagnet i571. As the next contacting portion of the set 35 of contact disks (equivalent to 8) engages the second brush from the right (Fig. 4), ground will in the same manner be supplied to the electromagnet H58, in the third unit of the cycle of rotation of the multiplying commutator ground will be connected to electromagnet I58, in the seventh unit the electromagnet H59, in the eighth unit of the electromagnet ltd, and in the ninth unit the electromagnet E88 will I have ground supplied thereto and will thereby be energized. All of the electromagnets i 58 to ifii and 242 which are energized as described hereinbefore, will continue to connect ground at 333 through theconductor 332, contacts of their associated transfer help relays until the ground connection to the transfer relays 358 and 3H is broken at brush l36 associated with the control contact disk lill. This break occurs as soon as the transfer has been completed and at this time the accumulator switch l8 will have the final product 7348012 registered therein since the product 123897 in the millions to tens registers of the accumulator switch l9 has been transferred thereto, and carries have been eifected where necessary in the same manner as they were effected in computing the units part of the problem.

The problem having been completed, the position of the brushes I to ill and 243 upon their associated banks of contacts indicatesthe final result. This record may be taken visually or since the brushes are connected to ground 342, 343, and 344, the other sides of the windings of which are connected through the conductor 345 to grounded battery at 345, thereby to energize the relays and connect ground through their contacts to the. conductors 353 to 361 and through-the conducting portions of the contact disks I13 and 288 to one side of the winding of the electromagnets 268 to 214, I55 to [GI and 242,

causing the brushes 218 to 284, I65 to Ill, and 243 to rotate to the position where they indicate zero, at which time the contact disks I13 and 288 will break the circuit, tie-energizing the relays and leaving the accumulator switch brushes in their zero or normal position.

Although a particular and specific description has been given of an electrical multiplication systemfor multiplying five digits by three digits, it is to be understood that the invention is to be limited only by the scope of the appended claims and that by adding similar apparatus and connecting it in the same manner as described hereinbefore, problems of any length might be expeditiousl'y computed;

What is claimed is:

1.'In a computing system, electrical circuits, factor storing means comprising circuit connections settable to represent a multiplicand and a multi-digit multiplier, rotatable. multiplying means for multiplying all digits of the multiplicand by one digit of the multiplierin each cycle of rotation, an accumulator for registering the' tens part of each product so effected, an accumulator for registering the units part of each product so effected, and means operable just subsequent to the multiplication of the digits in the multiplicand by the last digit in the multiplier for transferring the tens part of the product from the tens accumulator to the units accumulator.

2. In an electrical computing system, means for setting up multi-digit factors before the start of a computing operation, amultiplying means including elements representing the units part of computations of a plurality of digits and elements representing the tens part of the computations of the same digits, a plurality of accumulators sequentially operable means for completing electrical circuits through the setting up means and the multiplying means to transmit electrical impulses representing the result of the units part and the tens part of the computations to separate accumulators and means controlled by the sequentially operable means for establishing circuit connections and for automatically transferring results from one accumulator to another. i I

3. In a computing system, means for storing multi-digit factors of a mathematical problem,

ing means, means for accumulating the units part of the result (if a computation under control of said computing means, means for accumulating the tens part of the result under control of said computing means, and means for transferring the partial result from one of the accumulating means to the other accumulating mean to obtain the true result. 4. In a computing system, electrically controlled accumulators, means for storing a multidi'git multiplier and a multi-cligit multiplicand of av problem, total transfer circuits intermediate said accumulators, means controlled by the storing means for establishing contacts representing subproducts, and. sequential control means for establishing electrical circuits mrintroducing the units subproducts into'one accumulator and the tens subproducts into another accumulator and for subsequently completing said total transfer circuits to combine the subproducts-in one of the accumulators to obtain the complete result.

5. In an electrical computing system, means for storing a multi-digit multiplicand and amultidigit multiplier, multiplying means. associated with the setting up means, a left-hand component accumulator. a right-hand component accumulator, distributing means for establishing electrical circuit connections from the multiplying means to the accumulatorsto effect their operation, means for successively advancing the distributing means after the completion of the mul tiplication of each digit of the multiplier and all the digits of the multiplicand, transfer relays, means actuated with the distributing means for actuating the transfer relays, and means operable after the completion of the multiplication of all of the digits of the multiplier by all of the digits of the multiplicand andafter the opera-.

tion of the transfer relays for transferring a total from one accumulator to the other.

6. A multiplying machine with-a cyclically operated circuit establishing device which in one cycle of operation closes contacts representing,

the digits of all right-hand and left-hand components of partial products of the multiplication tables for the digits 1 to 9 inclusive, multi-denominational factor storing means for each factor for controlling said device, circuits for transmitting differentially timed multi-denominational product representing impulses under the conjoint control. of said storing means and the cyclically operated device, said impulses representing said products by their relative timing, and two accumulators'for receiving said right and left-hand components of partial products respectively. 7. A calculating machine for performing multiplica'tion including a plurality of partial product accumulating means, an impulse emitter which is cyclically operated in synchronism with the plural accumulating means to make onecomplete rotative cycle for one entering cycle of the said accumulating means, said emitterhaving a plurality of spots thereon to represent the digits of'the notation employed in the computation, factor entry means for both factors of the computation including contacts which are closed to store the digits of both factors to be computed, means under the control of one of the factor entry means for coordinating the emission of differentially timed impulses from the emitter to represent all partial products involving the first entered factor, means under the control of the other factor entry means for providing a multi-denominational selection of the differentially timed impulses representative of the particular partial products involving the other factor'which is of multi-denominational form.

8. In a multiplying machine in which an emitter and a factor storing means forstoring a multi-digit factor conjointly cause and control the impression upon two sets of lines of differentially timed impulses representative of all of the possible partial products of all of the digits of the notation times a digit of the entered factor, one set of lines for'impulses representative of right-hand components of partial products and the other set of lines for impulses representative of left-hand components, accumulating means, and multi-denominational factor entry impulse selecting means cooperating with both of the sets of lines to select out therefrom and denominationally allocate impulses representative of the right and left hand components of the partial products of the second factor times the first factor, and other partial product impulse lines extending directly from the last mentioned multidenominational selecting means to the accumulating means.

9. In a calculating machine having an emitter including contacts representative of the partial products of the multiplication tables for all digits for emitting impulses which are differentially timed so that by their individual timing they are individually representative of the digits of a notation, a plurality of digit lines leading therefrom, each of which receives an impulse pertaining to one digits only, means for storing a multidigit factor, a double set of selectors including contacts for storing another multi-digit factor, one set for right-hand components and the other set for left-hand components, said digit lines being associated with each set of selectors, and selectively operable electromagnetic coordinatin switching means controlledby said first storing means for rendering effective the emitter to send impulses over the digit lines as controlled by the second means for storing a multi-digit factor.

10. A multiplying machine including in combination, plural product receiving devices multidigit multiplier entry receiving means with an associated read out means, means including multiplier control multi-contact relays selectively called into action under the, control of the aforesaid read out means, dual multiplicand entry receiving devices to controlthe transmission of impulses representative of left-hand and right-hand components of partial products, an impulse emitter having a potential capability of emitting differentially timed impulses, representative of partial products lines leading from contacts of the multiplier relays to the dual multiplicand receiving devices through the emitter, product receiving means for receiving impulses transmitted from the emitter over said lines, and multi-contact column shift electrical means intermediate the dual multiplicand receiving means and the product receiving means and controlled for column shifting by the read out means of the multi plier entry receiving means.

11. In a computing system, a plurality of accumulators for accumulating results of computations, normally open electrical circuits interconnecting the accumulators for total transfer operations, a plurality of electrical transfer relays, electrical contacting means for operating the transfer relays to close the electrical circuits and emitter means for transmitting impulses over said electrical circuits to transfer a result from one accumulator to another accumulator.

. 12. In acomputing system, computing means, a plurality of accumulators controlled by the computing means forindicating results, means for transferring results from one accumulator to another accumulator including a normally ineffective continuously movable control commutator, and sequence means for enabling said continuously movable control commutator upon completion of entries into said accumulators to cause a transfer by said transfer means.

13. In a computing system, means for storing multi-digit factors, a multiplying means having a commutator controlled by the storing means for multiplying the stored factors in a continuous operation, a plurality of subproduct accumulators controlled by the multiplying means for accumulating subproducts, a denominational" distributor mechanism for controlling the entry of obtain a final result.

14. In a computing system, a plurality of accumulators for accumulating components of products, a multiplying commutator for controlling the accumulators, means for storing two multi-digit factors and for controlling the multiplying commutator in accordance with the entered factors, means for transferring a component of the product from one accumulator to another, andsequence control means for causing operation of said transferring means after said product components are accumulated.

15. In a computing system, electrical circuits, means for making circuit connections to set up a multiplicand and a multi-digit multiplier, continuously rotating multiplying means for multiplying all digits of the multiplicand by a successive digit of the multiplier in each cycle of rotation, an accumulator for registering the tens part of each product under control of said multplying means, an accumulator for registering the units part of each product under control of said multiplying means, and means effective upon completion of partial product registration for transferring the partial products from one accumulator to the other accumulator to obtain the final product.

16. In a computing system, a plurality of accumulators for accumulating results, normally open electrical circuits interconnecting the accumulators, a plurality of transfer relays, a plurality of transfer help relays, control timing means for operating the transfer relays for partially completing said circuits, and an emitter for energizing the transfer help relays to complete said electrical circuits to transfer a result from one accumulator to another accumulator.

17. In an electrical computing system, accumulators, means for actuating the accumulators, a cyclically operable multiplying device having a plurality of rotatable contact elements representing multiplication tables, means for pre--setting a multi-digit multiplicand and a multi-digit multiplier to establish circuits through the multiplying device in successive cycles thereof to control the actuating means for the accumulators, and means comprising devices operable with said multiplying device for establishing circuit connections to automatically transfer information from one accumulator to another.

18. A multi-denominational multiplying device comprising circuit controllers for storing a multidigit multiplier, circuit controllers for storing a; multi-digit multiplicand, a plurality of digital multiplier relays controlled by said first circuit controllers; a cyclically timed impulse emitter cooperating with both of the aforesaid controllers and with the plurality of relays so as to emit in one cycle thereof a plurality of differentially timed impulses which are representative of the products of a single digit of the multiplier and a multi-digit multiplicand, said circuit controllers and cyclically timed impulse emitter operating upon another cycle of operation of the cyclically timed impulse emitter for computation which involves said multi-digit multiplicand and another single digit of the multiplier, a plurality .of accumulators controlled by said timed impulses for. indicating partial results, and means for transferring the partial results from one accumulator to another accumulator to indicate the final result.

- NORBERT K. ENGST. 

